Alum. mig question

Date 02-19-2004 01:37

At work we are building some 12ft. long arcs made out of 1/8 alum. We are making 3 corner to corner joint welds in either the 1f or 2f position. We are running 3/64 (.047) 5356 wire using straight argon as shielding gas. My problem is getting the machine set so that there is not too much material on the joint. Everything gets ground after welding, so the smoother I make the weld the easier to grind. I started out using pulse mig, but switched to regular short arc mig, seems to run better and easier to fine tune. I still can't get it set where I am happy with it. I turn up the amperage and burn through, but still have too much build up. Turn it down and of coarse more build up. I am running about 13.3 volts and 330 ipm, seems to run the best there, but still a lot to grind. I programed a start voltage quite a bit higher to prevent the heavy build up prior to the wire getting warm. That seemed to work ok. The only thing I can think of is that the wire size is too large, but I don't think changing it is an option. We are unable to weld downhill due to the size of the parts. Any suggestions??? Or do I just need to grind away!!! Thanks

By flatjwl (*)

Date 02-19-2004 12:05

This is a tough one. Yes, your wire is much too big. Why are you using 5356? 4043 might wet in better and give somewhat less grinding, but .030 filler would help more. Perhaps your equipment will not allow the wimpy 4043 to feed?

By jdove55 (*)

Date 02-21-2004 01:01

We use 5356 wire because some of the jobs get an anodized finish after grinding. So using this wire eliminates the mistake of using 4043 and having it blacken when anodized. I talked with the lead about the wire size and he thought it would be a problem to have smaller wire size due to the wire not feeding well. We have a older push pull gun. A miller, it is a big machine gun looking gun. I haven't had any problems with the way the wire comes through at all yet. Today I found that increasing my travel speed worked the best. I have to really move though, to keep from getting too much buildup and if I go to fast I end up with poor fusion on one of the edges. I just either have to grind down the excess or tack where the non-fusion occurs. It is working ok. Is there much else I can do??

By bmaas1

Date 02-21-2004 02:26

Can you position the piece so that you have a slight downhill joint. Should help flatten it out.

Just a thought.

Brian J. Maas